Significant Asymptomatic Carotid Artery Stenosis Research Articles

Detection rates of asymptomatic carotid artery stenosis and atrial fibrillation by selective screening of patients without cardiovascular disease

BackgroundIndividuals with significant asymptomatic carotid artery stenosis (ACAS) and atrial fibrillation (AF) could benefit from specific interventions to prevent heart attack and stroke, but are often clinically ‘silent’. We aimed to determine detection rate of ACAS and AF by screening, targeting a population at increased cardiovascular risk. MethodsData on adults who attended voluntary and self-funded commercial screening clinics in the United States or the United Kingdom between 2008 and 2013 were used. The Atherosclerotic Cardiovascular Disease (ASCVD) risk equation was applied to each participants and detection rates of targeted screening for ≥50% ACAS and AF to those at highest risk of CVD was assessed. ResultsAmong 0.4 million individuals between 40 and 80 years, without CVD, 6191 (1.6%) had ACAS and 1026 (0.3%) had AF. Selective screening of participants with a predicted 10-year CVD risk of ≥20% identified 40% of ACAS cases, a prevalence of 3.7%, leading to a number needed to screen (NNS) of 27, as well as 39% of AF cases, a prevalence of 0.6%, with a NNS of 170. Selective screening of those with a predicted 10-year CVD risk of ≥15% identified 54% of ACAS cases, a prevalence of 3.3%, and an NNS of 31, as well as 51% of AF cases, a prevalence of 0.5%, with an NNS of 195. ConclusionsSelective screening for ACAS and AF implemented in ASCVD risk assessment greatly reduces the NNS when compared with population-level screening with detection rates of ACAS and AF substantially greater in people at higher predicted CVD risk.

Stroke incidence between stenting and endarterectomy for asymptomatic carotid artery stenosis

A best evidence topic has been constructed using a described protocol. The three-part question addressed was: In patients with significant asymptomatic carotid artery stenosis (ACAS), Does Carotid artery stenting (CAS) has a peri-procedural lower Stroke rate, As compared to Carotid endarterectomy (CEA)? The outcomes assessed were the stroke rate in the two management modalities. The best evidence showed no statistically significant difference between CAS and CEA regarding the peri-procedural and the long-term non-procedural stroke incidence. However, in high-risk patients, CAS may be a better option.

Prevalence of asymptomatic carotid artery stenosis in Chinese patients with lower extremity peripheral arterial disease: a cross-sectional study on 653 patients

ObjectiveThis study aimed to investigate the prevalence and identify predictive factors of asymptomatic carotid artery stenosis (ACAS) in Southern Chinese patients with peripheral arterial disease (PAD).DesignA cross-sectional study.Setting and participantsA...

Treatment strategies for asymptomatic carotid artery stenosis in the era of lipid-lowering drugs: protocol for a systematic review and network meta-analysis

IntroductionCarotid endarterectomy (CEA), carotid artery stenting (CAS) and best medical therapy (BMT) are the major treatments used for significant asymptomatic carotid artery stenosis (ACAS, ≥50%). However, the widespread use of...

Correlation between significant asymptomatic carotid artery stenosis and severity of peripheral arterial occlusive disease in the lower limb: a retrospective study on 200 patients

BackgroundThe aim of this study was to evaluate the correlation between significant asymptomatic carotid artery stenosis (ACAS) and severity of peripheral arterial occlusive disease (PAOD) in the lower limb, and to investigate the risk factors for significant ACAS in patients with lower limb PAOD.MethodsTwo hundred patients with lower limb PAOD were retrospectively reviewed. Baseline data, medical history and potential risk factors were collected. Lower limb PAOD was classified as stage IIA, stage IIB, stage III and stage IV. The carotid artery stenosis was classified as significant ACAS and non-significant ACAS. Multiple logistic regression estimated odds ratio of the risk factors.ResultsCompared to patients with non-significant ACAS, the patients with significant ACAS were significantly older in age and had greater percentage of cigarette-smoking andalcohol beverage consumption, and higher levels of total cholesterol and fibrinogen. There was no significant difference in sex, diabetes, hypertension, coronary heart disease and triglyceride between the two groups. The prevalence rate of significant ACAS increased with the stage of lower limb PAOD and with age. Advanced age and hypercholesteremia were risk factors for significant ACAS in this cohort. The prevalence rate of stroke increased with ACAS stage.ConclusionThe results suggested that the prevalence rate of significant ACAS was positively correlated with the severity of lower limb PAOD and age. Advanced age and hypercholesteremia appeared to be potential risk factors for significant ACAS in patients with lower limb PAOD.

Effect of a significant asymptomatic unilateral carotid artery stenosis on outcomes in patients undergoing coronary artery bypass grafting.

Occurrence of a stroke is a major concern in patients undergoing coronary artery bypass grafting (CABG). It remains uncertain whether significant asymptomatic carotid artery stenosis (CAS) is associated with stroke incidence in such patients. To investigate the incidence of cerebrovascular events, myocardial infarction (MI), and death in patients with a significant asymptomatic CAS undergoing CABG. We prospectively evaluated 123 consecutive patients with documented carotid artery duplex Doppler ultrasound examination who underwent isolated CABG. Patients with a significant (≥ 60%) asymptomatic unilateral CAS (n = 35) were compared with those without a significant CAS (n = 88) to assess the rates of stroke, MI and mortality after CABG. No significant differences between patients with a significant asymptomatic unilateral CAS and those without a significant CAS in regard to age (p = 0.5955), presence of hypertension (p = 0.2343), diabetes (p = 0.5495), smoking (p = 0.7891), serum creatinine (p = 0.47) and left ventricular systolic function as evaluated by ejection fraction (p = 0.3789). No cerebrovascular events, MI and deaths occurred during the first 30 days postoperatively. At 12 months, no differences were seen between the groups in the incidence of MI (p = 0.1005) and mortality (p = 0.3959). However, a trend towards higher stroke incidence was noted among patients with a significant asymptomatic unilateral CAS (p = 0.0692). The primary combined endpoint (stroke, MI, and mortality) occurred in 40% of patients with a significant asymptomatic unilateral CAS and 17.05% of patients without a significant CAS (p = 0.0097). Linear regression analysis showed an association between significant asymptomatic unilateral CAS and stroke (p = 0.0041), and between significant asymptomatic unilateral CAS and the primary end point (p = 0.0475). The presence of a significant asymptomatic unilateral CAS does not increase the risk of stroke, MI and mortality within 30 days after CABG but is was associated with an increased risk of cardiovascular events during the first 12 months postoperatively.

Validation of Two Different Grading Schemes to Identify Patients With Asymptomatic Carotid Artery Stenosis in General Population

Identification of significant asymptomatic carotid artery stenosis (ACAS) is important because of potential stroke-risk reduction offered by carotid endarterectomy. We present an external validation of two previously developed scoring schemes designed to identify patients with ACAS. We used the data from the Cardiovascular Health Study (CHS)-a cohort study of cardiovascular risk factors, for external validation. Carotid Doppler ultrasound was performed in study participants. Two grading schemes, which used age more than 65 years, current smoking, and history of coronary artery disease and hyperlipidemia as predictors for ACAS, were validated using this dataset. A total of 5,449 persons (mean age 72 +/- 5 years; 42% men; and 84% white) were screened. The overall prevalence of ACAS of > or =50% was 4.2%. The prevalence of ACAS in the highest risk category was 19% in both stratification schemes. The stratification remained effective in the white sub-population (P < .001), but was not significant in the African American population (P > .05). Both schemes were effective in identifying persons with ACAS among general population aged 65 years or greater. A subset with a prevalence of ACAS of greater than 20% can be identified using these schemes making screening cost-effective among white population.

In patients undergoing cardiac surgery does asymptomatic significant carotid artery stenosis warrant carotid endarterectomy?

A best evidence topic in cardiovascular surgery was written according to a structured protocol. The question addressed was whether asymptomatic significant carotid artery stenosis (ASCAS) warrants carotid endarterectomy (CEA) in patients undergoing cardiac surgery. 128 Papers were found using the reported search, of these 10 presented represent the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses of these papers are tabulated. We conclude that low risk, younger patients with a significant asymptomatic carotid artery stenosis should be considered for carotid endarterectomy at some stage. There is, however, no strong evidence that this must be performed prior to, or during CABG.

Who should be screened for asymptomatic carotid artery stenosis? Experience from the Western New York Stroke Screening Program.

Identification of significant asymptomatic carotid artery stenosis (ACAS) is important because of the stroke-risk reduction observed with carotid endarterectomy. The authors developed and validated a simple scoring system based on routinely available information to identify persons at high risk for ACAS using data collected during a community health screening program at various sites in western New York. A total of 1331 unselected volunteers without previous stroke, transient ischemic attack, or carotid artery surgery were evaluated by personal interview and duplex ultrasound. The main outcome measure was carotid artery stenosis > 60% by duplex ultrasound. In the derivation set (n = 887), 4 variables were significantly associated with ACAS > 60%: age > 65 years (odds ratio [OR] = 4.1, 95% confidence interval [CI] = 2.6-6.7), current smoking (OR = 2.0, 95% CI = 1.2-3.5), coronary artery disease (OR = 2.4, 95% CI = 1.5-3.9), and hypercholesterolemia (OR = 1.9, 95% CI = 1.2-2.9). Three risk groups (low, intermediate, and high) were defined on the basis of total risk score assigned on the basis of the strength of association. The scheme effectively stratified the validation set (n = 444); the likelihood ratio and posttest probability for ACAS in the high-risk group were 3.0 and 35%, respectively, and in the intermediate and low-risk groups were 1.4 and 20% and 0.4 and 7%, respectively. Routinely available information can be used to identify persons in the community at high risk for ACAS. Doppler ultrasound screening in this subgroup may prove to be cost-effective and have an effect on stroke-free survival.

Prevalence of asymptomatic carotid stenosis in patients undergoing infrainguinal bypass surgery.

The prevalence of asymptomatic carotid stenosis in patients with lower-extremity ischemia is unknown. This report represents the largest carotid screening program to date of patients undergoing leg bypass. Patients undergoing infrainguinal bypass from 1987 through 1993 on the vascular surgery service at Oregon Health Sciences University, Portland, underwent routine carotid duplex examinations to detect the presence of asymptomatic carotid stenosis. During the study period, 352 patients underwent infrainguinal revascularization for ischemia, of whom 225 (64%) had no prior carotid surgery, carotid arteriography, or cerebrovascular symptoms. There were 117 men and 108 women, with a mean age of 67 years. The indication for surgery was limb salvage in 67% and claudication in 33% of patients. Sixty-four patients (28.4%) who required lower-extremity revascularization had hemodynamically significant asymptomatic carotid artery stenosis or occlusion; 12.4% had stenosis of 60% or greater, the qualifying level for randomization in the Asymptomatic Carotid Atherosclerosis Study. Based on these findings, eight patients with carotid stenosis of 80% or greater underwent elective carotid endarterectomy. There were no postoperative neurologic events in the 225 leg bypass patients. By multivariate logistic regression analysis, the presence of carotid bruit (P < .001) and the presence of rest pain (P = .006) were associated with carotid stenosis of 50% or greater. Limiting screening to patients with carotid bruit, limb salvage indications for surgery, and/or advanced age excluded significant numbers of patients with stenosis; thus, these were not effective screening strategies. Screening carotid duplex scanning is indicated in patients who require lower-extremity revascularization.

Influence of aspirin in the management of asymptomatic carotid artery stenosis

Purpose: Aspirin therapy is recommended commonly for symptomatic extracranial carotid artery occlusive disease. However, its role in the management of asymptomatic carotid artery stenosis has not been reported previously.Methods: In 11 clinical centers during the period 1983 to 1991, 444 adult male patients with significant asymptomatic carotid artery stenosis (≥50% arteriographically) were randomized to receive optimal medical management including aspirin plus carotid endarterectomy (n = 211) or optimal medical management alone (n = 233). At the conclusion of the study (mean follow-up time 47.9 months), at the time of a patient's death, or at occurrence of a neurologic end point, 16% of patients (n = 72) were not taking any aspirin, 51% (n = 226) had been converted to receiving enteric-coated aspirin, and only 33% (n = 146) were taking plain aspirin (27% at reduced dosage). Among patients from the medical group, 37 (16%) of 233 were not taking any aspirin and formed the basis for this retrospective analysis of the group for which no control population was available.Results: Mortality rates in this group were not significantly different for patients not taking aspirin as compared with the rates for those taking aspirin, although patients not taking aspirin had a higher incidence of myocardial infarction (27%) as compared with patients taking aspirin (8%), p < 0.05. The incidence of ipsilateral neurologic events for patients not taking aspirin as compared with that for patients who were taking aspirin, respectively, was as follows: stroke, 13.5% and 8.7%, p > 0.05; stroke and transient ischemic attack, 37.8% and 17.3%, p < 0.05. No significant differences were observed in stroke severity scores for patients taking or not taking aspirin.Conclusion: These data suggest that patients with significant asymptomatic carotid artery stenosis who are intolerant of aspirin have a higher incidence of neurologic events than those patients able to tolerate the drug.